Air pump



FIG. 1 is a front, top perspective view of an air pump, showing my new design;

FIG. 2 is a rear, bottom perspective view thereof;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a rear elevation view thereof;

FIG. 5 is a left side elevation view thereof;

FIG. 6 is a right side elevation view thereof;

FIG. 7 is a top plan view thereof; and,

FIG. 8 is a bottom plan view thereof.

The broken lines in the figures illustrate portions of the air pump that form no part of the claimed design. 

CLAIM The ornamental design for an air pump, as shown and described. 